DE2046476C2 - Cyclic 2-alkyl glycerol acetals, processes for their preparation and use of these compounds as herbicides - Google Patents

Description

R CH ₂ -OR ³

C C

CH ₂ -O

CH ₂ -O

R ⁴

in which:

R is a C, - to C ₆ -alkyl group, R ^{1 is} a hydrogen atom, a methyl,

Ethyl, butyl, bromomethyl, phenylethyl, ethoxy, benzyl, furyl, pyridyl or a phenyl group which is optionally so substituted by a methyl or methoxy group or a chlorine atom,

R ^{2 is} a hydrogen atom or a methyl

group or

R ¹ and R ^J together form a tetramethylene, penta-

methylene or hexamethylene group,

Y is a benzyl group, optionally

is substituted on the benzene ring by one or more fluorine or chlorine atoms or a methyl group or a phenyl group, a benzoyl, a phenyl or a furfuryl group,

R ³ and R ⁴ each represent a hydrogen atom, a methyl group, a phenyl or benzyl group, or

R- 'and R ⁴ together represent a tetramethylene, pentamethylene or hexamethylene group

mean. 2. 4-Benzyloxymethyl-2,2-dimethyl-4-n-propyl-

1,3-dioxolane.

3. 't-Benzyloxymethyl ^^ - dimethyM-n-ethyl-1,3-dioxolane.

4. S-Benzyioxy-S-methyl ^ -phenyl-l ^ -dioxane.

5. 4 - Benzyloxymethyl -4 - methyl -1,3 - dioxolane-2-spirocyclohexane.

6. 5-Benzyloxy-5-methyl-1,3-dioxane-2-spirocyclohexane.

7. A method for the preparation of the compounds according to claim 1, characterized in that one in each case in a manner known per se

a) the corresponding hydroxy derivative with an organic halogen compound of the formula Hal - Y, in which Y is an optionally substituted hydrocarbon group or a Acyl group and Hal denotes a halogen atom or

b) the corresponding halopropane derivative with a salt of the formula MO-Y, in which M is an alkali atom, converts or

c) the corresponding diol derivative with a carbonyl linkage, an acetal or ketal, the is derived therefrom, reacts in the presence of an acid.

8. Use of the compounds according to claim 1, optionally together with a carrier and / or a surface-active substance and / or other common additives as herbicides.

The invention relates to the cyclic 2-alkyl-glycerol acetals characterized in more detail in the main claim of the general formulas I and II, a process for their preparation and use of these compounds as herbicides. These compounds have herbicidal, plant growth regulating and fungicidal properties Properties. <, o

The following compounds are particularly preferred because of their high biological activity.

4-benzyloxymethyl-2,2-dimethyl-4-n-propyl- 1,3-dioxolane;

4-benzyloxymethyl-2,2-dimethyl-4-ethyl- 1,3-dioxolane;

5-benzyloxy-5-methyl-2-phenyl-1,3-dioxane;

4-Benzyloxymethyl-4-methyl-1,3-dioxolane-Hai - Y

2-spirocyclohexane;

S-benzyloxy-5-methyl-1, S.

hexane.

It should be noted that many of the 2-alkyl-glycerol derivatives according to the invention have gsometric and / or optical isomers. The invention relates to both the individual isomers and mixtures of these isomers. The invention also relates to a process for the preparation of the 2-alkyl-glycerol derivatives of the formula I, in which none of the groups Y is a hydrogen atom, which is characterized in that the corresponding monohydroxy derivative is mixed with an organohalogen derivative of the formula

in which Y is an optionally substituted hydrocarbon or acyl group and Hal a halogen atom, preferably a chlorine atom, converts Das Hydroxy derivative is preferably in the form of a salt, preferably an alkali salt such as the sodium salt is used and the reaction is preferably carried out in an organic solvent such as toluene.

In certain cases, e.g. B. the group Y is a phenyl or furfuryl group, it is cheaper to use another method, which is characterized in that a suitable halogen propane derivative with a salt of the formula

MO-Y

IV

in the M an alkali atom, favorably a sodium atom, means, converts The reaction is preferably carried out in a polar organic solvent such as Dimethyl sulfoxide carried out.

The compounds according to the invention can also are produced? by the corresponding diol with a carbonyl compound of the formula ■

O = C

(V)

25th

30th

or an acetal or ketal derived from such a carbonyl compound in the presence of an acid, advantageously an inorganic acid such as hydrochloric acid, or an arylsulfonic acid; £, such as p-toluenesulfonic acid, reacts. The reaction is preferably carried out in an aromatic hydrocarbon ^: (T, e.g. benzene or toluene, as a solvent.

As mentioned above, the 2-alkylglycerol derivatives according to the invention show herbicidal and plant growth regulating properties and the invention therefore also relates to the use of the inventive Compounds, optionally together with a carrier and / or a surface-active one Substance and / or other usual additives, as herbicides.

The term "carrier" as used herein means a substance that is inorganic or organic and may be synthetic or natural with which the active ingredient is mixed or formulated to the application to seeds, soil or other objects to be treated or its storage, the transport or to make handling easier. The carrier can be solid or liquid. Each commonly used to manufacture Substance used by pesticidal agents can be used as a carrier.

Suitable solid supports are natural and synthetic clays and silicates, e.g. B. natural silicates such as Diatomaceous earth; Magnesium silicates, e.g., talc; Magnesium aluminum silicates, z. B. attapulgites and vermiculites; Aluminum silicates, e.g. B. kaolinites, montmorillonites and mica; Calcium carbonates; Calcium sulfate; synthetic hydrated silicas and syn calcium or aluminum synthetic silicates; Elements such as B. carbon and sulfur; natural and synthetic Resins such as B. coumarone resins, polyvinyl chloride and styrene polymers and copolymers; fixed Polychlorophenols; Bitumen; Waxes such as B. beeswax, paraffin wax and chlorinated mineral waxes; solid fertilizers, e.g. superphosphates.

Examples of suitable liquid carriers are water, alcohols, such as, for example, isopropanol, glycols; Ketones like z. B. Acetoii, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; Ether; aromatic hydrocarbons, such as. Benzene, toluene and xylene; Petroleum fractions, such as B, kerosene, light mineral oil; chlorinated hydrocarbons, such as carbon tetrachloride, Perchlorethylene, trichloroethane, including liquefied normally gaseous compounds. Mixtures of different liquids are often suitable

The surfactant can be an emulsifier or a dispersant or a wetting agent. It can be non-ionic or ionic. Any surfactant as it is normally used to manufacture used by herbicides or insecticidal agents can be used. Examples of suitable Surface-active substances are the sodium or calcium salts of polyacrylic acids and lignosulfonic acids; the condensation products of fatty acids or aliphatic amines or amides containing at least 12 carbon atoms in the molecule with ethylene oxide and / or propylene oxide; Fatty acid esters of glycerol, sorbitan, sucrose or pentaerythritol; Condensates of these compounds with ethylene oxide and / or propylene oxide; Condensation products of Fatty alcohols or aylphenols, e.g. B. p-OctylphenoI or p-octylcresol with ethylene oxide and / or propylene oxide; Sulfates or sulfonates of these condensation products; Alkali or alkaline earth salts, preferably Sodium salts of sulfuric or sulfonic acid esters with at least 10 carbon atoms in the molecule, e.g. B. Sodium lauryl sulfate Sodium secalkyl sulfates, sodium salts of sulfonated! Castor oil and sodium alkylarylsulfonates such as sodium dodecylbenzenesulfonate and polymers of ethylene oxide and copolymers of ethylene oxide and propylene oxide.

The agents according to the invention can be prepared as wettable powders, dusts, granules, solutions, emulsifiable concentrates, emulsions, suspension concentrates and aerosols. Wettable powders are normally prepared to contain 25.50 or 75% by weight of the toxin and usually, in addition to the solid carrier, 3 to 10% by weight of a dispersant and, if necessary, 0 to 10% by weight of stabilizer (s ) and / or additives such as penetrants or tackifiers. Dusts are normally produced as dust concentrates with a similar composition to the wettable powders, but without dispersants and when used are diluted with further solid carrier material so that an agent is produced which normally contains V ₂ to 10% by weight of the poisonous substance. Granules are normally made to have a particle size of 0.148 mm to 1.98 mm (10 to 100 BS mesh) and they can be made by agglomeration or impregnation processes. In general, granules V contain ₂ to 25% by weight of toxin and 0 to 10% by weight of additives such as stabilizers, modifiers for the slow release of the toxin and binders. Emulsifiable concentrates normally contain, in addition to the solvent and, if necessary, additional solvent, 10 to 50% (w / v) toxin, 2 to 20% (w / v) emulsifiers and 0 to 20% (w / v). / Vol.) Suitable additives such as stabilizers, penetranules and corrosion inhibitors. Suspension concentrates are made so that one

a stable, non-sticking, flowable product is obtained, which is usually 10 to 75% by weight toxin, 0.5 to 15% by weight of dispersant, 0.1 to 10% by weight of suspending agent such as protective colloids and thioxotropic agents, 0 to 10% by weight of suitable additives such as defoamers, corrosion inhibitors, stabilizers, penetrants and tackifiers, and water as a carrier or contains an organic liquid in which the toxin is substantially insoluble; certain organic solids or inorganic salts can be in dissolved in the wearer to prevent sedimentation or as an anti-freeze agent for water.

The agents according to the invention can contain other ingredients, such as. B. protective colloids such as gelatin, Glue, casein, gumraen, cellulose ether and polyvinyl alcohol; thioxotropic agents, e.g. B. bentonites, sodium phosphates; Stabilizers such as ethylenediaminetetraacetic acid, urea, triphenyl phosphate and Tackifiers, e.g. B. contain non-volatile oils.

Aqueous dispersions and emulsions such as are used, for. B. obtained by diluting a wettable powder or emulsifiable concentrate according to the invention with water are also within the scope of the present invention. These emulsions can be in the form of water-in-oil or in the form of oil-in-water emulsions and can be thick Have a mayonnaise-like consistency.

The invention is illustrated in more detail by the following examples

example 1 4-benzyloxymethyl-2,2,4-trimethyl-1,3-dioxolane

a) 2-methylglycerin

20.0 g of methallyl alcohol, 20.0 g of aluminum oxide and 2.0 g of tungstic acid in 100 ml of water were heated to 60 ° C. and then 31.6 ml of a 30% (w / v) solution of hydrogen peroxide were slowly added admitted. During the addition the mixture was kept at 60 ° C by cooling. After the addition the mixture was held an additional hour at 60 ⁰ C and then two hours to 95 ° C. After cooling, the mixture was filtered and the filtrate by two columns containing Amberlite IRA 400 * or Permutit Zeo-Carb. · 225 contained, directed. The solvent was removed and crude 2-methylglycerol was obtained, which was not further purified.

b) 4 * hydroxymethyl! -2,2,4-trimethyl-1,3-dioxolane

50 g of 2-methylglycerol, 150 ml of acetone, 1.5 g of p-toluenesulfonic acid and 150 ml of petroleum ether (b.p. 40 to 60 ¹ C) were put together for 24 hours under two Vigreux columns, each 40 cm in length, and a Dean-and-Stark Water separator heated. After the reaction mixture had cooled, 1.5 g of molten sodium acetate were added. The suspension was stirred at room temperature for 30 min and then nitrated. The solvents were removed from the filtrate under reduced pressure and the residue was fractionally distilled. 4-hydroxymethyl-2,2,4-trimethyl-1,3-dioxolane was obtained as a colorless liquid bp . 7V ° C / 16mbar.

c) 4-Benzyloxyiiv: 'hyl-2,2,4-trimethyl-1,3-oxolane

10 g of 4-hydroxymethyl-2,2,4-trimethyl-1,3-dioxolane were mixed with 3 g of a 50% strength Dispersion of sodium hydride in oil in 150ml dry toluene added dropwise after complete In addition, the solution was heated under reflux conditions until hydrogen no longer evolved. Within 15 minutes, 7.85 g of benzyl chloride were added to the refluxing Solution was added dropwise and the solution was then refluxed for a further 3 hours The solution was then cooled, washed three times with 30 ml of water each time, and the solvent removed under reduced pressure. The oily residue was fractionally distilled received the desired product as a colorless liquid, boiling point 80 ° C./0.2 mm Hg.

analysis

Calculated for C ₁₄ H ₂₀ O ₃ : Found:

C 71.3; H 8.5% C 71.3; H 8.7%

Example 2

4-benzyloxymethyl-2,2-dimethyl-4-n-propyl-1,3-dioxolane

2-n-propyl glycerine

50 ml of a 37 to 41% solution of formaldehyde and 53 g of dimethylamine hydrochloride were mixed, a clear solution being formed to which 50 g of valeric aldehyde were slowly added. The solution was for 1 hour at 55 ° C and then held 22 to 24 hours at 70 ⁰ C heated The crude product was separated by steam distillation, dissolved in 100 ml of methanol and at 30 to 40 ⁰ C with 5.25 g of sodium borohydride in 45 ml aqueous methanol reduces After de.n end of the reduction 120 of a 13% aqueous solution were added ml of sodium hydroxide and the mixture heated for 1 hour at 80 ⁰ C. the solution was cooled and extracted with ether the dried extracts were concentrated and the oily residue dried with magnesium sulfate and fractionally distilled. 2-methylenepentan-1-ol was obtained. Bp. 61 to 63 ° C / 2O mbar. Starting from 2-methylen-penlan-l-ol, the desired product iris colorless liquid was obtained via a series of reactions which correspond to those of Examples la) to c). Bp. 97 ° C / 0.4 mbar.

analysis

Calculated for C ₁₆ H ₂₄ O ₃ : Found:

C 72.7; H 9.1% C 72.4, H 9.2%

Example 3

According to procedures as described in Examples 1 and 2, white were tere compounds produced, the physical data and analyzes of which are given in Table 1 below.

Table 1 link

boiling point ° C / mb »r

analysis

4-Benzyloxymethyl-4-n-hexyl-2,2-dimethyl-1,3-dioxolane

4- (4'-chlorobenzyloxymethyl) -2,2,4-trimethyl-1,3-dioxolane

4- (4'-methylbenzyloxymethyl) -2,2,4-trimethyl-1,3-dioxolane

4- (3'-methylbenzyloxymethyl) -2,2,4-trimethyl-1,3-dioxolane

4- (3 ', 4'-dichlorobenzyloxymethyl) -2,2,4-trimethyl-1,3-dioxolane

Ί-0 ^. / Limpthvl-

1,3-dioxolane

4-benzyloxymethyl-4-isopropyl-2,2-dimethyl-1,3-dioxolane

4-benzyloxymethyl-2-isobutyl-2,4-dimethyl-1,3-dioxolane

4-benzyloxymethyl-2-ethyl-2,4-dimethyl-1,3-dioxolane

4-benzyloxymethyl-2,4-dimethyl-2-phenyl-1,3-dioxolane

4- {4'-fluorobenzylyoxymethyl) -2,2,4-trimethyl-1,3-dioxolane

4- {2 ', 3', 6'-trichlorobenzyloxymethyl) -2,2,4-trimethyl-1,3-dioxolane

4-benzyloxymethyl-4-methyl-2-phenyl-1,3-dioxolane

124 / 0.4. Calculated for Ci ₉ H ₃₀ O ₃ : C 74.5; H 9.8%

Found: C, 74.5; H 9.9%

94 / 0.13 Calculated Door C ₁₄ Hi ₉ O ₃ Cl: C 62.0; H 7.0%

Found: C, 62.3; H 7.2%

91 / 0.4. Calculated for C ₁₅ H ₂₂ O ₃ : C 72.0; H 8.8%

Found: C, 71.6; H 8.8%

90 / 0.4. Calculated for C ₁₅ H ₂₂ O ₃ : C 72.0; H 8.8%

Found: C, 72.0; H 8.6%

121 / 0.4. Calculated for C ₁₄ H ₁₁ O ₃ Cl ₂ : C 55.1; H 5.9%

Found: C, 55.9; H 6.0%

oA / n α Calculated for CHG 'C72C ° ii ^oo * ^/

Found: "'"' ⁵ " ²² ^ C72] 2; H9! O%

99 / 0.53. Calculated for C ₁₆ H ₂₄ O ₃ : C 72.7; H 9.1%

Found: C, 73.9; H 9.0%

103 / 0.4. Calculated for Ci ₇ H ₂₆ O ₃ : C 73.4; H 9.4%

Found: C, 73.3; H 9.4%

98 / 0.67. Calculated for Ci ₅ H ₂₂ O ₃ : C 72.0; H 8.8%

Found: C, 72.9; H 9.1%

125 / 0.20. Calculated for C ₁₉ H ₂₂ O ₃ : C 76.5; H 7.4%

Found: C, 76.7; H 7.7%

83 / 0.4. Calculated For Ci ₄ Hi ₉ O ₃ F: C 66.1; H 7.5%

Found: C, 66.3; H 7.8%

132-138 / Calculated for C ₁₄ H ₁₇ O ₃ O ₃ : C 49.4; H 5.0%

0.53 Found: C 49.0; H 5.1%

136 / 0.20. Calculated for C ₁₈ H ₂₀ O ₃ : C, 76.1; H 7.0%

Found: C, 76.4; H 7.4%

Example 4 4-Benzyloxymethyl-4-methyl-2-p-tolyl-1,3-dioxolane

6.5 g of S-benzyloxy ^ methylpropane-l ^ -diol, 4.0 g p-Toluylaldehyde and p-Toluenesulfonic acid in 200 ml Benzene were heated together under reflux conditions until no more water was released. the The cooled solution was washed first with 5% strength potassium carbonate solution and then with water. the Solution was dried and the solvent removed under reduced pressure. The liquid residue was purified by chromatography on alumina with benzene as the eluant

Table 2

Desired product n% 1.5361. analysis

Calculated for C ₁₉ H ₂₂ O ₃ : C, 76.5; H 7.4% Found: C 76.6; H 7.5%

Example 5

Corresponding to the previous examples specified procedures, further compounds were produced, their physical data and analyzes in are given in Table 2 below.

link Kp. ^O C / mbar
or n _D analysis C 72.6;
C 7V; H 7.0%
H 7.1% 4-BenzyIoxymethyl-2- <4-methoxyphenyl) -
4-methyl-1J-dioxolane η? 1.5422 Calculated for C) ₉ H ₂₂ O ₄ :
Found: C 67.8;
C 68.0; H 5.9% 4-Benzyloxymetriyl-2- {4-chlorophenyl) -4-methyl-
1 ^ 3-dioxolane n? ⁵ 1.5482 Calculated for Ci ₁ Hi ₉ O ₃ O:
Found: C 70.0;
C 70.6; H 6.6%
H 6.8% 4-Benzyloxymethyl-2- {fur-2-yl) -4-methyl-
1,3-dioxolane nf ⁵ 14198 Calculated for C ₁ ^ H ₁₁ O ₄ :
Found:

to

continuation Kp. T / mbar
or H _n analysis for C _n H ₂₄ O ₃ : C.
C. 74.0; H
74.4; H 8.7%
8.9% * link 102 / 0.20 Calculated
Found: for Ci ₇ H ₁₁₁ NO ₃ : C.
C. 71.6; H
N
71.7; H
N 6.7;
4.9%
6.8;
4.8% > / ' 4-benzyloxymethyl-4-methyl-1,3-dioxolane
2-spirocyclohexane n _'D ■■ 1.5388 Calculated
Found: door C _2n H ₂₄ O ,: C.
C. 77.0; H
77.2: H 7.7%
7.9% I. 4-benzyloxymethyl-4-methyl-2- (2-pyridyl) -
1,3-dioxolane 130 / 0.13 Calculated
Found: for C ₁₆ H ₂₂ O ,: C.
C. 73.4; H
73.4; H 8.4%
8.4% I. 4-benzyloxymethyl-2-benzyl-2,4-dimethyl-
1,3-dioxolane 107 / 0.27 Calculated
Found: for C ₂ OH ₂₄ O ₃ : C.
C. 77.0; H
76.7; H 7.7%
7.8% 4-benzyloxymethyl-4-methyl-1,3-dioxolane
2-spirocyclopentane 151 / 0.13 Calculated
Found: door C ₁₂ Hi ₆ O ₃ : C.
C. 69.2; H
69.6; H 7.7%
7.7% 4-Benzyloxymethyl-4-methyl-2- (2-phenylethyl) - nj, 1.5008 Calculated
Found: for Ci ₈ H ₂₆ O ₃ : C.
C. 74.5; H
74.1; H 9.0%
9.1% 4-Ben7yloxymethyl-4-methyl-1,3-dioxolane nj, ' 1.5069 Calculated
Found: 4-benzyloxymethyl-4-methyl-1,3-dioxolane
7-snirncvcInhentan

Example 6
4-Benzyloxymethyl-2,4-dimethyl-1,3-dioxolane

5.0g S-Benzyloxy ^ -methylpropane-1- ^ -diol, 3.0g 1,1-diethoxyethane and p-toluenesulfonic acid were used heated with stirring to 110 to 115 ° C until no more alcohol was evolved. The mixture then became Heated to 140 to 145 ° C for 15 min. After cooling, the mixture was dissolved in ether and the resulting Solution washed with 5% potassium carbonate solution and then with water. The solution was dried over anhydrous magnesium sulfate and the solvent removed under reduced pressure. A liquid was obtained which, on distillation, gave the desired product. Bp. 81 to 82 ° C / 0.4 mbar.

analysis

Calculated for C _n H ₁₈ O ₃ :
Found:

C 70.3; H 8.1%
C 70.6; H 8.0%

Example 7

Following the procedure given in Example 6, the following compounds were prepared.

^ Benzyloxymethyl ^ -bromomethyl- ^ methyl-

1,3-dioxolane

Bp. 114 ° C / 0.20 mbar.

Analysis Calculated for C ₁₃ H ₁₇ O ₃ Br: C, 51.9; H 5.6% 4-benzyloxymethyl-2-ethoxy-4-methyl-1,3-dioxolane bp 108 ° C / 0.4 mmHg

analysis

Calculated for C ₁₄ H _2n O ₄ : C, 66.8; H 7.9% λ Found: C 66.5; H 8.4%

Example 8 4-Phenoxymethyl-2,2,4-trimethyl-1,3-dioxolane

5.0 g of 4-chloromethyl-2.2,4-trimethyl-1,3-dioxolane and 3.7 g of sodium phenoxide, made from phenol and sodium hydride, in 90 ml of dimethyl sulfide were heated together at 140 ° C for 4 hours. The reaction mixture was diluted with water and the

aqueous solution extracted with ether. The ether extracts were dried and the solvent under reduced pressure Pressure removed. A liquid was obtained which, after distillation, the desired product revealed. Bp. 83.5 ° C / 0.4 mbar.

analysis

Calculated for C ₁₃ H ₁₈ O ₃ : C, 70.3; H 8.1% Found: C 70.7; H 8.1%

Found:

C 51.9; H 6.0%

4-Benzyloxymethyl-2-benzyl-4-methyl-1,3-dioxolane Bp. 134 ° C / 0.27 mbar.

Analysis calculated for Ci ₉ H ₂₂ O ₃ : C 76.6; H 7.4%

Found:

C 77.0; H 7.4%

Example 9

Following the procedure described in Example 8, the following compounds were prepared

4-methyl-4-phenoxymethyl-2-phenyl-1,3-dioxolane in" 1.5393)

analysis

Calculated Door C ₁₇ H ₁₈ O ₃ : C 75.6; H 6.7% Found: C, 75.8; H 6.9%

4-Furfuryloxvmethvl-2,2,4-trimethyl-1 _r 3-dioxolane bp. 73.5 ° C / 0.5 mm Hg

analysis

Calculates Rjr
Found:

Example 11

C 63.7; H 8.0%
C 64.0; H 8.0%

Example 10
4-Benzoyloxymethyl-2,2,4-trimethyl-1,3-dioxolane

A solution of 14.0 g of benzoyl chloride in 30 ml of dry carbon tetrachloride was added with stirring to a cooled solution containing 14.6 g of 2-hydroxymethyl-2,2,4-trimethyl-1,3-dioxolane and 7.9 g of pyridine contained in 70 ml of carbon tetrachloride. The solution was stirred overnight and then refluxed for 1 hour. The cooled solution was nitrated and 200 ml of ether were added to the filtrate. The ether solution was washed with 1% hydrochloric acid, with saturated sodium bicarbonate solution and finally with water and dried. The solvent was removed under reduced pressure and the residue was fractionally distilled. The mbar over at 1o6 ° C / O, 53 solution was cooled to -50 ⁰ C and triturated with petroleum ether. The desired product was obtained. Mp. 29 to 30 ^° C.

analysis

5-benzyloxy-5-methyl-2-phenyl-1,3-dioxane

25.05 g of 2-methylglycerol and 26.0 g of benzaldehyde were mixed at room temperature and 100 to 200 ml of dry hydrogen chloride were passed through the Mixture passed through. Then 500 ml of benzene was added to the mixture and the water azeotroped removed within 18 hours while a ίο very weak stream of hydrogen chloride flows through the Solution was passed through. The solvent was then removed under reduced pressure and the crude product recrystallized from cyclohexane. Pure 5-hydroxy-5-methyl-2-phenyl-1,3-dioxane was obtained. ι i The thus obtained hydroxy compound was with benzyl chloride implemented in a corresponding manner as described in Example Ic). The desired one was obtained Product. Mp 56 ° C.

20 Calculates door C ₁₈ Hj _n O.,:
Found:

C 76.1; H 7.0%
C 76.0; H 7.1%

Example 12

Analogous to the processes for the preparation of the dioxolane derivatives described in the preceding examples other dioxane derivatives were produced.

For C ₁₄ Hi ₈ O ₄ : C 67.2; H 7.2%
Found: C, 67.2; H 7.3% their physical constants and
jo following table are given. . 93 / 0.4 analysis for Ci ₄ H ₂₀ O ₃ : Analyzes in the Table 3 ■ 1.5199 Calculated
Found: for C ₁₇ H ₂₄ O ₃ : link Mp. ⁰ C,
Bp ° C / mbar
or n _n . 117 / 0.20 Calculated
Found: for C ₁₆ H ₂₂ O ₃ : 5-benzyloxy-2,2,5-trimethyl-1,3-dioxane Kp. 1.5411 Calculated
Found: RJrC ₂₀ H ₂₄ O ₃ : C 71.3; H
C 71.2; H 8.5%
8.7% 5-benzyloxy-5-methyl-1,3-dioxane
2-spirocyclohexane 1.5189 Calculated
Found: for C ₁₈ H ₂₆ O ₃ : C 73.8; H
C 73.6; H 8.7%
8.6.% S-Benzyloxy-S-methyl-l ^ -dioxan
2-spi roey clopentane Kp Calculated
Found: C 73.4; H
C 73.1; H 8.4%
8.6% 5-benzyloxy-2-benzyl-2,5-dimethyl-
1,3-dioxane "H C 77.0; H
C 77.0; H 7.7%
7.7% 5-benzyloxy-5-methyl-1,3-dioxane
2-spirocycloheptane "b" C 74.5; H
C 74.7; H 9.0%
9.2%

Herbicidal effect

55

To investigate the herbicidal activity, the compounds according to the invention were compared to a representative set of plants examined:

Corn, Zea mays (M); Oats, Avena sativa (H); Ray- μ grass, LoIi um perenne (RG); Peas, Pisum sativum (E); Flaxseed, Linum usitatissium (L); Mustard, Sinapis alba (S); and sugar beet, Beta vulgaris (Z).

These studies were divided into two groups namely in those pre-emergence, and those after emergence of the plants. The pre- emergence tests consisted of spraying a liquid preparation of the compounds onto the ground in which the seeds of the above-mentioned plants had been sown shortly beforehand. Post-emergence examinations include two types of examinations, soaking the soil and spraying the leaves. When the soil was soaked, the soil in which the young plants of the species specified above grew was soaked with a liquid preparation which contained a compound according to the invention, and in the foliar spray tests the young plants were sprayed with such a preparation

The soil used in the experiments was a with Steam sterilized, modified John Bmes Compost Mixture with half of the peat in the loose

Mass had been replaced by vermiculite.

The preparations used in the investigations were prepared by adding solutions of Compounds in acetone containing 0.4% by weight of an alkylphenol / ethylene oxide condensate available under (also known as Triton X-155 *) with Water diluted. In the tests where the soil or the leaves were sprayed, the acetone solutions were diluted with an equal volume of water and the resulting preparations are applied in two different doses, corresponding to 10 or 1 kg of active substance per hectare in a volume corresponding to 4001 per hectare. In the trials where the Roden was soaked, the acetone solution was diluted with water to 155 volumes and the resulting Preparation applied in a dose equivalent to an amount of 10 kg of active substance per hectare in one Volume of approximately 30001 per hectare.

During the attempts before emergence a

4. _n Vr, "

look for emergent a non-treated

Soil with young plants used as a comparison. The herbicidal effects of the compounds were

7 days after spraying the leaves and watering ken the floor and 11 days after spraying the üodens determined visually and given according to a 0 to 9 scale. The value 0 means that the treated plants were not attacked, the value 2 shows a decrease in the fresh weight of

ίο Stems and leaves of plants of about Zi · / ·, the value 5 means a decrease of about 55%, the value 9 a decrease of 95% etc.

The results of these tests are given in Table 4.

When investigating certain compounds, instead of oats, rice, Oryza sativa (R) and used instead of ryegrass Bernyard grass, Echinochioa crusgalli (BG). The results of these tests are given in Table 5.

Claims (1)

Claims; 1. Cyclic 1-alkyl glycerol acetals of the general formulas I and II CH ₂ -OR ¹ R C COR ² YOH ₂ C